External HD sometimes doesn't attach, how to re-probe?

Jens Schweikhardt schweikh at schweikhardt.net
Tue May 10 09:17:39 UTC 2016

hello, world\n

I have this disk in an Icy Box connected via USB3:

da0 at umass-sim0 bus 0 scbus11 target 0 lun 0
da0: <ST4000DX 001-1CE168 CC44> Fixed Direct Access SCSI device
da0: 400.000MB/s transfers
da0: 3815447MB (7814037168 512 byte sectors)
da0: quirks=0x2<NO_6_BYTE>

Every now and then (1 in 10 or so), when I power-up the Icy Box, the
drive spins up, but the device nodes do not appear. I then try to
"camcontrol rescan all", restart devd and devfs, but it has no effect.
Invariably I end up power-cycling the Icy Box, which always works.

Is there a different way to "re-probe" disks connected via USB when
they fail to attach on the first try?


Jens Schweikhardt http://www.schweikhardt.net/
SIGSIG -- signature too long (core dumped)

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